• Smart Structures and Systems
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• v.21 no.3
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• pp.287-303
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• 2018

Applications of energy harvesting from mechanical vibrations is becoming popular but the full potential of such applications is yet to be explored. This paper addresses this issue by considering an application of energy harvesting for the dual objective of serving as an indicator of structural health monitoring (SHM) and extent of control. Variation of harvested energy from an undamaged baseline is employed for this purpose and the concept is illustrated by implementing it for active vibrations of a pipe structure. Theoretical and experimental analyses are carried out to determine the energy harvesting potential from undamaged and damaged conditions. The use of energy harvesting as indicator for control is subsequently investigated, considering the effect of the introduction of a tuned mass damper (TMD). It is found that energy harvesting can be used for the detection and monitoring of the location and magnitude of damage occurring within a pipe structure. Additionally, the harvested energy acts as an indicator of the extent of reduction of vibration of pipes when a TMD is attached. This paper extends the range of applications of energy harvesting devices for the monitoring of built infrastructure and illustrates the vast potential of energy harvesters as smart sensors.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.5
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• pp.885-891
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• 2012

The synchronous flash of a marine lantern, differentiated from the flash pattern of other risk indicators, supports the safe sailing of vessels. General marine lanterns flash according to the flash protocol through sensing the day and the night. Thus, there can be time error over time and the marine lantern does not synchronously flash as a whole. To resolve this problem, this study designed LED marine lantern based on constant-current system using synchronous flash technique enabling all marine lanterns to keep its time based on GPS satellite time. Also we suggested a radiation method with an effective heat emission performance in the restricted and closed space of a marine lantern.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.11
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• pp.2067-2072
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• 2016

Recently, due to the development of attack techniques that can circumvent existing information protection systems, continuous threats in a form unrecognized by the user have threatened information assets. Therefore, it is necessary to support the prompt responses to anticipated attempts of APT attacks, bypass access attacks, and encryption packet attacks, which the existing systems have difficulty defending against through a single response, and to continuously monitor information protection systems with a defense strategy based on Indicators of Attack (IOA). In this paper, I suggest a centralized intelligent information protection system to support the intelligent response to a violation by discerning important assets through prevention control in a performance impact assessment about information properties in order to block the attack routes of APT; establishing information control policies through weakness/risk analyses in order to remove the risks in advance; establishing detection control by restricting interior/exterior bypass networks to server access and monitoring encrypted communications; and lastly, performing related corrective control through backup/restoration.

• The Journal of Internal Korean Medicine
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• v.41 no.3
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• pp.362-413
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• 2020

Objectives: The purpose of this research is to examine the recent clinical research trends on the efficiency of traditional herb medicine (THM) on gastroesophageal reflux disease (GERD), and to provide clinical evidence of herbal medicine, Banhasasin-tang or Banxiexin decoction by using a systemic review and meta-analysis of randomized trials (RCTs). Methods: In this study, randomized controlled trials (RCTs) were included that verified effects of traditional herbal medicine (THM), including a Banxia-xiexin-tang decoction, as a treatment for GERD. A study of the literature in Chinese and Korean databases was performed for papers published from January 1, 2010, to January 1, 2020. The selected literature was assessed by Cochrane's risk of bias (RoB). Results: A total of 90 RCTs met the inclusion criteria. Except for four RCT studies, all studies identified the effect of a Banxia-xiexin-tang decoction in the treatment of GERD. The effectiveness of treatment was significantly higher in the intervention group than in the control group, as shown through various evaluation indicators, including the reflux disease diagnostic questionnaire (RDQ). Adverse effects were reported in 22 articles (24.44%). Conclusions: Treatment with Banhasasin-tang, or a Banxia-xiexin-tang decoction, was found to be effective in treating GERD. However, due to the low quality of available studies, the significance of this conclusion is somewhat limited. This study could serve as a foundation for further clinical studies on the development of diagnosis and treatment methods for GERD based on Korean medicine.

• Geomechanics and Engineering
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• v.13 no.5
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• pp.861-879
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• 2017

Coal and gas outburst is a serious dynamic disaster that occurs during coal mining and threatens the lives of coal miners. Currently, coal and gas outburst is commonly predicted using single indicator and its critical value. However, single indicator is unable to fully reflect all of the factors impacting outburst risk and has poor prediction accuracy. Therefore, a more accurate prediction method is necessary. In this work, we first analyzed on-site impacting factors and precursors of coal and gas outburst; then, we constructed a Fisher discriminant analysis (FDA) index system using the gas adsorption index of drilling cutting ${\Delta}h_2$, the drilling cutting weight S, the initial velocity of gas emission from borehole q, the thickness of soft coal h, and the maximum ratio of post-blasting gas emission peak to pre-blasting gas emission $B_{max}$; finally, we studied an FDA-based multiple indicators discriminant model of coal and gas outburst, and applied the discriminant model to predict coal and gas outburst. The results showed that the discriminant model has 100% prediction accuracy, even when some conventional indexes are lower than the warning criteria. The FDA method has a broad application prospects in coal and gas outburst prediction.

• Clinical Nutrition Research
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• v.5 no.4
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• pp.279-289
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• 2016

The adequate dietary intake is important to maintain the nutritional status of the patients after pancreatic cancer surgery. This prospective study was designed to investigate the dietary intake and the nutritional status of the patients who had pancreatic cancer surgery. Thirty-one patients (15 men, 16 women) were enrolled and measured body weight, body mass index (BMI), nutritional risk index (NRI), and Malnutrition Universal Screening Tool (MUST). Actual oral intake with nutritional impact symptoms recorded on the clinical research foam at every meal and medical information were collected from electronic medical charts. The rates of malnutrition at admission were 45.1% (14/31) and 28.9% (9/31) by NRI and MUST method, respectively, but those were increased to 87% (27/31) and 86.6% (26/31) after operation on discharge. The median values of daily intake of energy, carbohydrates, fat, and protein were 588.1 kcal, 96.0 g, 11.8 g, and 27.0 g, respectively. Most patients (n = 20, 64.5%) experienced two or more symptoms such as anorexia, abdominal bloating and early satiety. There were negative correlations between C-reactive protein (CRP) levels and the intake of total energy, protein, fat, and zinc. The rates of malnutrition were increased sharply after surgery and the dietary intake also influenced the inflammatory indicators. The results suggested that need of considering special therapeutic diets for the patients who received pancreatic surgery.

• Health Policy and Management
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• v.29 no.3
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• pp.277-287
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• 2019

Background: Diabetes is known as one of the most important ambulatory care sensitive conditions. This study purposed to assess the status of continuity of care (COC) and diabetes-related avoidable hospitalizations (DRAHs) of a group of middle- and old-aged patients and to observe the relationship of the two elements by the two age groups. Methods: This study utilized the National Health Insurance Service's National Sample Cohort data and the subjects are diabetes patients of 45 and over, classified into two groups of 'middle-aged'(45-64 years) and 'old-aged'(${\geq}65years$) patients. The dependent variable was DRAHs, which was defined in accordance with the definition of the Organization for Economic Cooperation and Development "Health Care Quality Indicators" project. COC, as an independent variable, is measured by the COC index in this study. Two-part model (multi-variate and multi-level analyses) was utilized. Results: Factors associated with the status and the number of DRAHs differed by each age group. Meanwhile, the two-part model showed that higher COC was associated with a lower risk of preventable hospitalizations in both middle- and old-aged groups. Conclusion: Study findings can provide health policy insights and implications in order to strengthen the primary care system for further improvement of diabetes management, especially for middle- and old-aged groups.

• Herbal Formula Science
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• v.29 no.4
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• pp.285-295
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• 2021

Objective : This systematic review was conducted to investigate the effect of herbal medicine on Helicobacter pylori(H. pylori) infection compared to amoxicillin included synthetic drugs. Methods : Relevant randomized controlled trials(RCTs) which were published prior to December 26, 2020, were collected using PubMED database. Risk of bias evaluation and data extraction were done independently by two reviewers, and the third reviewer reassessed mismatching parts. Results : Two RCTs testing two different herbal medicines against synthetic drugs solitary treatment or synthetic drugs with placebo for herbal medicine were included. One study reported that there was no significant difference between the eradication rate of synthetic drugs and the herbal medicine. The other study did not report the eradication rate of the herbal medicine. One study reported histologic severity, the other reported dyspepsia score as efficacy indicators. There was no adverse event reported in all studies. However, the number of included RCTs was too small, the quality of reported data was not enough to verify efficacy of herbal medicine, and there were some methodological problems. Conclusion : It was difficult to conclude that solitary treatment of herbal medicine was as effective as amoxicillin included synthetic drugs for H. pylori infection.

• Journal of Environmental Health Sciences
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• v.47 no.2
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• pp.144-154
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• 2021

Objectives: This study was intended to identify hazard contribution by region, media, and chemical by calculating a hazard-based index using pollutant release and transfer register (PRTR) data. Methods: PRTR data for the period 2011 to 2016 was analyzed to examine the regional trends in toxic releases in terms of quantity and to create a corresponding hazard-based index. For the hazard-based index, the Risk-Screening Environmental Indicators (RSEI) Model was used. Results: The results of the trend analysis show that total releases decreased slightly, but health hazard levels increased consistently. According to the outcome of regional contribution analysis of the hazard-based index, Chungcheongnam-do, Jeollabuk-do and Gyeonggi-do Provinces showed a high ratio in the index for air and water release pollutants, while Gyeongsangbuk-do and Gyeongsangnam-do Provinces showed a high ratio in the index of soil release and waste transfer pollutants. Also, as a result of the analysis of the top ranked substances in the hazard-based index, it was found that chromium, cobalt and its compounds, and ethylene oxide contributed greatly to air release substances, while chromium, benzene, and lead and its compounds contributed greatly to water release substances. Conclusion: These results showed considerable disparities between total release and health hazard levels, especially in the analysis of contribution by regions and by chemical substance. Therefore, the hazard-based index should be used both to support a more comprehensive and robust approach to screening of chemicals for environmental health policy and for management.

• Safety and Health at Work
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• v.9 no.4
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• pp.454-461
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• 2018

Background: Working conditions and psychosocial work factors have acquired an important role explaining the well-being and performance of professional drivers, including those working in the field of public transport. This study aimed to examine the association between job strain and the operational performance of public transport drivers and to compare the expositions with psychosocial risk at work of three different types of transport workers: taxi drivers, city bus drivers, and interurban bus drivers. Method: A sample of 780 professional drivers was drawn from three transport companies in Bogota (Colombia). The participants answered the Job Content Questionnaire and a set of sociodemographic and driving performance questions, including age, professional driving experience, work schedules, and accidents and penalties suffered in the last 2 years. Results: Analyses showed significant associations between measures of socio-labor variables and key performance indicators such road traffic accidents and penalties. Furthermore, multiple linear regression analysis contributed to explain significantly suffered accidents from key variables of the Job Demand-Control model, essentially from job strain. In addition, throughout post-hoc analyses, significant differences were found in terms of perceived social support, job strain, and job insecurity. Conclusion: Work stress is an issue that compromises the safety of professional drivers. This research provides evidence supporting a significant effect of job strain on the professional driver's performance. Moreover, the statistically significant differences between taxi drivers, city bus drivers, and interurban bus drivers in their expositions to work-related stress suggest the need for tailored occupational safety interventions on each occupational group.